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The tropism of influenza viruses for the human respiratory tract is a key determinant of host-range, and consequently, of pathogenesis and transmission. Insights can be obtained from clinical and autopsy studies of human disease and relevant animal models. Ex vivo cultures of the human respiratory tract and in vitro cultures of primary human cells can provide complementary information provided they are physiologically comparable in relevant characteristics to human tissues in vivo, e.g. virus receptor distribution, state of differentiation. We review different experimental models for their physiological relevance and summarize available data using these cultures in relation to highly pathogenic avian influenza H5N1, in comparison where relevant, with other influenza viruses. Transformed continuous cell-lines often differ in important ways to the corresponding tissues in vivo.  相似文献   
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Introduction: Fetal kidney length vs biparietal diameter (BPD) and femur length (FL) were comparatively evaluated and the role of fetal kidney length in estimating gestational age was determined in the second and third trimesters. Materials and methods: The study was carried out on 199 women with singleton uncomplicated pregnancies attending the outdoor patient department (OPD) for routine ultrasound fetal biometry. Fetal kidney length was measured biweekly, between 18 weeks and 38 weeks of gestation. Linear regression models for estimation of gestational age were derived from biometric indices (BPD and FL) and kidney length. Result: The earliest age at which fetal kidney could be seen sonographically was the 18th week of gestation with the mean kidney length of 12 ± 1.31 mm. The mean sonographic kidney length at the 38th week of gestation was 40.4 ± 1.71 mm, indicating that the mean fetal kidney length increases as pregnancy progresses from 18 weeks to 38 weeks of gestation. Conclusion: The best linear regression model for estimating fetal gestational age is femur length, kidney length, and biparietal diameter in that order, with standard error of ±3.85 days, ±8.04 days, and ±8.75 days, respectively.  相似文献   
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Sport Sciences for Health - Social isolation due to the coronavirus disease 2019 (COVID-19) pandemic has reduced physical activity levels in both men and women. The identification of barriers to...  相似文献   
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The coronavirus disease 2019 (COVID-19) pandemic presents a significant global public health challenge. One in five individuals with COVID-19 presents with symptoms that last for weeks after hospital discharge, a condition termed “long COVID”. Thus, efficient follow-up of patients is needed to assess the resolution of lung pathologies and systemic involvement. Thoracic imaging is multimodal and involves using different forms of waves to produce images of the organs within the thorax. In general, it includes chest X-ray, computed tomography, lung ultrasound and magnetic resonance imaging techniques. Such modalities have been useful in the diagnosis and prognosis of COVID-19. These tools have also allowed for the follow-up and assessment of long COVID. This review provides insights on the effectiveness of thoracic imaging techniques in the follow-up of COVID-19 survivors who had long COVID.  相似文献   
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Patel  Urvish  Malik  Preeti  Shah  Dhaivat  Patel  Achint  Dhamoon  Mandip  Jani  Vishal 《Journal of neurology》2021,268(1):240-247
Journal of Neurology - Due to pro-inflammatory and hypercoagulation states, COVID-19 infection is believed to increase the risk of stroke and worsen the outcomes of the patients having pre-existing...  相似文献   
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Rodin et al.'s study (2020) on the belief, knowledge and attitudes about tics amongst health professionals in Uganda is a preliminary yet an important step towards challenging the current thinking amongst clinicians and academics working with tics, which is that tics are hardly seen in or are absent in the sub-Saharan African population and it has been psotulated that this phenomenon is considered to be explained by genetics.  相似文献   
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